Adding flag to specify the used memory pressure strategy

chromeos/chromeos_switches.cc

Index: chromeos/chromeos_switches.cc
diff --git a/chromeos/chromeos_switches.cc b/chromeos/chromeos_switches.cc
index 43042cf68c90ab519493bd5e4114f5bb97fad211..055eaab800ae24bdcda7a7648f0a08a68c27c0c5 100644
--- a/chromeos/chromeos_switches.cc
+++ b/chromeos/chromeos_switches.cc
@@ -213,6 +213,10 @@ const char kLoginProfile[] = "login-profile";
 // Specifies the user which is already logged in.
 const char kLoginUser[] = "login-user";
 
+// The memory pressure thresholds selection which is used to decide when a
+// memory pressure event needs to get fired.
+const char kMemoryPressureThresholds[] = "memory-pressure-thresholds";
+
 // Enables natural scroll by default.
 const char kNaturalScrollDefault[] = "enable-natural-scroll-default";
 
@@ -292,5 +296,31 @@ bool WakeOnWifiEnabled() {
   return !base::CommandLine::ForCurrentProcess()->HasSwitch(kDisableWakeOnWifi);
 }
 
+base::MemoryPressureObserverChromeOS::MemoryPressureThresholds
+GetMemoryPressureThresholds() {
+  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
+          kMemoryPressureThresholds)) {
+    return base::MemoryPressureObserverChromeOS::
+        MEMORY_PRESSURE_THRESHOLD_DEFAULT;
+  }
+  const std::string option =
+      base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
+          kMemoryPressureThresholds);
+  if (option == "1") {
+    return base::MemoryPressureObserverChromeOS::
+        MEMORY_PRESSURE_THRESHOLD_CONSERVATIVE;
+  }
+  if (option == "2") {
+    return base::MemoryPressureObserverChromeOS::
+        MEMORY_PRESSURE_THRESHOLD_AGGRESSIVE_CACHE_DISCARD;
+  }
+  if (option == "3") {
+    return base::MemoryPressureObserverChromeOS::
+        MEMORY_PRESSURE_THRESHOLD_AGGRESSIVE_TAB_DISCARD;
+  }
+  return base::MemoryPressureObserverChromeOS::
+      MEMORY_PRESSURE_THRESHOLD_AGGRESSIVE;
+}
+
 }  // namespace switches
 }  // namespace chromeos